OFFSET
1,2
COMMENTS
With A001411 as main input and counting the symmetrical shapes separately, higher terms can be computed efficiently (see formula). - Bert Dobbelaere, Jan 07 2019
LINKS
Bert Dobbelaere, Table of n, a(n) for n = 1..60
Ed Pegg, Jr., Illustrations of polyforms
Eric Weisstein's World of Mathematics, Polyedge
FORMULA
CROSSREFS
KEYWORD
nonn,hard
AUTHOR
Ed Pegg Jr, May 13 2009
EXTENSIONS
a(13)-a(19) from Joseph Myers, Oct 03 2011
More terms using formula by Bert Dobbelaere, Jan 07 2019
STATUS
approved